A252672 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 5 6 or 7

656, 750, 808, 1010, 1648, 2554, 4038, 7108, 11589, 18742, 33497, 55048, 90043, 161568, 265519, 437213, 784708, 1287805, 2129537, 3818659, 6254869, 10373871, 18577187, 30367195, 50480530, 90263879, 147262314, 245263852, 437902643

Offset

1,1

Comments

Column 1 of A252679

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 22*a(n-3) -203*a(n-6) +1029*a(n-9) -3177*a(n-12) +6346*a(n-15) -8664*a(n-18) +8513*a(n-21) -5980*a(n-24) +2593*a(n-27) -305*a(n-30) -595*a(n-33) +664*a(n-36) -372*a(n-39) +162*a(n-42) -40*a(n-45) +8*a(n-48) for n>57

Example

Some solutions for n=4
..3..1..3....0..2..0....3..1..3....2..0..3....1..1..0....1..1..0....2..0..0
..1..1..0....1..2..3....3..3..0....1..0..1....0..1..1....0..1..1....2..3..2
..0..1..1....2..0..0....2..0..0....1..1..0....3..2..0....0..2..3....0..0..2
..0..2..0....0..1..1....3..0..3....2..0..0....0..0..0....1..1..0....2..0..0
..1..1..0....2..0..3....3..3..0....1..3..1....1..1..3....0..1..1....1..3..2
..3..1..1....2..3..0....2..0..0....1..1..0....2..2..1....2..2..3....1..0..1

Crossrefs

Sequence in context: A220057 A194653 A252671 * A252679 A252680 A233898

Adjacent sequences: A252669 A252670 A252671 * A252673 A252674 A252675

Keyword

nonn

Author

R. H. Hardin, Dec 20 2014

Status

approved